Roll src/third_party/skia 77af4ecd3546..5f2807b71e71 (3 commits) (#8866)

https://skia.googlesource.com/skia.git
/%2Blog/77af4ecd3546..5f2807b71e71

git log 77af4ecd3546e38e8b6ca6e0efbc6b9df65dc83a..5f2807b71e71a92bd7df1ed3527f0be8208a4c96 --date=short --no-merges --format=%ad %ae %s
2019-05-06 halcanary@google.com Clean up CanvasTest.cpp some more
2019-05-06 bungeman@google.com Clean up CanvasTest.cpp macros.
2019-05-06 brianosman@google.com Revert "Support GL_EXT_draw_buffers"

The AutoRoll server is located here: https://autoroll.skia.org/r/skia-flutter-autoroll

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+/master/autoroll/README.md

If the roll is causing failures, please contact the current sheriff (robertphillips@google.com), and stop
the roller if necessary.

DEPS

@@ -23,7 +23,7 @@ vars = {
   'fuchsia_git': 'https://fuchsia.googlesource.com',
   'github_git': 'https://github.com',
   'skia_git': 'https://skia.googlesource.com',
-  'skia_revision': '77af4ecd3546e38e8b6ca6e0efbc6b9df65dc83a',
+  'skia_revision': '5f2807b71e71a92bd7df1ed3527f0be8208a4c96',
 
   # When updating the Dart revision, ensure that all entries that are
   # dependencies of Dart are also updated to match the entries in the

ci/licenses_golden/licenses_skia

-Signature: fa0a95425b4c480b2922ca74481bf3c1
+Signature: 7d4390705a77cfdc4b2f2d0d38e25993
 
 UNUSED LICENSES: